A rectangular emerald and diamond cluster ring

An octagonal emerald and diamond cluster ring, the octagonal-cut emerald weighing 3.58 carats, accompanied by GCS report stating to be of Colombian origin, millegrain-set to a diamond cluster surround, the twenty-four old-cut diamonds estimated to weigh 0.24 carats in total, to a platinum shank with diamond encrusted shoulders, gross weight 4 grams, circa 1950,